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Chemia znikającego alkoholu: Twoje ciało winowajcą czy ofiarą?

Kowalczuk Dominika, Brzózka Bartosz

Analit

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2023

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Nr 13

28--31

PL

Alkohol, dzięki swoim właściwościom stosowany jest jako popularna wśród społeczeństwa używka, należy jednak brać pod uwagę fakt możliwości pojawienia się nieprzyjemnych skutków jego działania na organizm w postaci kaca kolejnego dnia. Odpowiedzialny za to jest między innymi jeden z metabolitów alkoholu, a mianowicie aldehyd octowy. Jego poziom po spożyciu alkoholu etylowego jest zależny od naszego poziomu dehydrogenazy aldehydowej, w większości przypadków jest on za niski by nie odczuwać objawów kaca. Do typowych objawów tej przypadłości należą: zmęczenie, pragnienie, ból głowy, problemy ze snem, podrażnienie przewodu pokarmowego, problemy sensoryczne, problemy z nastrojem, pocenie i drżenie. Na intensywność kaca ma wpływ kilka czynników i to zarówno przed spożywaniem jak i po. Ale jedynym w stu procentach skutecznym sposobem jest nie picie alkoholu lub ograniczenie spożycia do absolutnego minimum. Pomimo tego, że istnieje kilka mitów o cudownych sposobach na kaca takich jak mocna kawa, zimny prysznic, kolejność picia alkoholi lub klin, to żaden z nich nie jest tak naprawdę skuteczny i co najwyżej łagodzi część objawów.

EN

Alcohol in our culture allows us to make friends, but do not overdo it because we can experience a hangover the next day. One of the metabolites of alcohol, namely acetaldehyde, is responsible for this. Its level after consuming ethyl alcohol depends on our level of aldehyde dehydrogenase, in most cases it is too low not to feel the symptoms of a hangover. Typical symptoms of this condition include fatigue, thirst, headache, sleep problems, gastrointestinal irritation, sensory problems, mood problems, sweating and tremors. Several factors affect the intensity of a hangover, both before and after eating. But the only one hundred percent effective way is not to drink alcohol or to limit consumption to the absolute minimum. Although there are several myths about hangover miraculous remedies such as strong coffee, cold showers, the order of drinking alcohols or wedges, none of them are really effective and only relieve some of the symptoms.

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Enancjoselektywna enzymatyczna desymetryzacja katalizowana oksydoreduktazami. Dehydrogenazy w reakcji redukcji. Część I

Kołodziejska R., Karczmarska-Wódzka A., Tafelska-Kaczmarek A., Studzińska R., Wróblewski M., Augustyńska B.

Wiadomości Chemiczne

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2014

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[Z] 68, 9-10

763--782

EN

Enzymes act as biocatalysts whether are also mediating in all anabolic and catabolic pathways, playing an extremely important role in the cells of all life forms. Catalytic potential of oxidoreductases is most commonly used in reduction reactions. Dehydrogenases and reductases catalyze the reversible desymmetrization reactions of meso and prochiral carbonyl compounds and alkenes. The oxidoreductase- catalyzed reactions require cofactors to initiate catalysis. In most cases, it is nicotinamide adenine dinucleotide (NADH) or its phosphorylated derivative (NADPH), which acts as a hydride donor. The necessity of employing expensive cofactors was, for the long time, one of the main limitations to the use of dehydrogenases. This problem was solved by developing a regeneration system of a cofactor in the reaction environment. Various systems are used for the cofactor recycling. In the case of a carbonyl compound reduction, an irreversible oxidation of formic acid to carbon dioxide is most frequently used. In this paper, selected examples of whole-cell and isolated enzymes applications in the carbonyl compound reduction are discussed. The application of baker’s yeast, microorganisms and dehydrogenases in enantioselective enzymatic desymmetrization (EED) of prochiral ketones leads to a broad spectrum of chiral alcohols used as intermediates in the syntheses of many pharmaceuticals and compounds presenting a potential biological activity.

3

Dehydrogenazy alkoholowe pochodzenia mikrobiologicznego : właściwości i ich zastosowanie

Szczepańska E., Boratyński F.

Wiadomości Chemiczne

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2014

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[Z] 68, 11-12

1049--1071

EN

Biotransformations involve mainly microorganisms or individual enzymes applied to catalyze chemical reactions [1]. This field of science is particularly important, because it allows to obtain optically active compounds, which are valuable raw materials for pharmaceutical (Fig. 3, Fig. 6, Fig. 20, Fig. 21), wood and paper (Fig. 18), food (Fig. 4), textile (Fig. 12), cosmetic (Fig. 14) industries and environmental protection (Fig. 19). Oxidoreductases, in particular alcohol dehydrogenases (E.C.1.1.1.1, ADH) are valuable biocatalysts enabling to obtain enantiomerically pure products. These enzymes, commonly found in nature, catalyze both oxidation and reduction reactions [3]. Described dehydrogenases descend from mesophilic, psychrophilic and thermophilic microorganisms. The increasing application of thermophiles is due to their exceptional resistance against heat and organic solvents. The article describes and explains how microbial ADH’s interact with NAD+/NADH or NADP+/NADPH and present those enzymes which catalyze reactions with both forms of cofactors. The alcohol dehydrogenases from yeast are particularly commonly used [9–14]. Bacterial enzymes, among them ADH isolated from Thermoanaerobacter brockii [47–51], are widely distributed too. In addition, the literature describes a number of (R)-specific ADH’s from Lactobacillus kefir [40–42], L. brevis [45, 46], Leisofonia sp. [20] Pseudomonas fluorescens [23] and (S)- -specific ADH’s from Rhodococcus erythropolis [15, 16], Thermus sp. [30], Sulfolobus solfataricus [23, 28] and many others.

4

Short Hydrogen Bonds in the Catalytic Mechanism of Alcohol and Lactate Dehydrogenases

Leskovac V., Trivić S., Popović M.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 12

1925-1943

EN

The survey of crystallographic data from the ProteinData Bank for 63 enzyme complexes with substrates indicates the presence of many short hydrogen bonds in the active site of alcohol (EC 1.1.1.1) and lactate (EC 1.1.1.27) dehydrogenases, which are formed between the substrate, or substrate analog, and the acid-base catalyst in enzyme. In the case of alcohol dehydrogenase enzymes, the short hydrogen bonds are clustering in the active site exactly at the bond-breaking position between the substrate and the acid-base catalyst in enzyme, with the frequency of 70-100%. In lactate dehydrogenase enzymes, this frequency is much lower and amounts to 15-30%. This result strongly suggests that the active site of alcohol dehydrogenases is designed to bind the substrate by short hydrogen bonds exactly at the bond-breaking position.

5

Natural stereospecific hydrogen isotope transfer in alcohol dehydrogenase-catalysed reduction

Zhang B., Pionnier S.

Nukleonika

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2002

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Vol. 47,suppl.1

29-31

EN

The enantiomeric purity of natural alfa-monodeuterated enantiomers, (R) and (S) ethanol-1-d1, in the alcohol produced by sugar fermentation with yeast was studied by 2H NMR using their esters derived from optical mandelic acid. The results of isotope tracing experiments show that the transfer pathways of the two enantiotopic hydrogens of the methylene group are different. It was observed that (S)-deuterium comes only from the medium water. The (R)-deuterium transfered by NADH in alcohol dehydrogenase reduction of the acetaldehyde is of complex origin. Some of them originates from carbon bound hydrogen of the sugar, especially from C(4) position of glucose and most of them comes from water. Only a small portion of the NADH deuterium is incorporated indirectly from water through enzyme catalysed exchange between the pro-S site of NADH and flavin. When a carbonyl compound (ethyl acetoacetate) was reduced under the same conditions during the alcoholic fermentation, among the NADH-transfered deuterium, only a small portion comes from water while most comes from the unexchangeable positions of the glucose.